JPH10286781A - Large nut attaching/detaching device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device in which attaching/detaching work of a special nut of a large size and heavy weight can be safely and easily performed. SOLUTION: A slide table is provided on a carriage 2 to be horizontally movable longitudinally, and an elevation table 19 is provided on it to be freely capable of elevation. A turn table 27 is provided on the elevation table 19 to be horizontally movable, and a nut N is placed on it to be rotated. The elevation table 19 is elevated by an air cylinder 18, and the turn table 27 is rotated normally and inversely by an air motor 37, so the nut N is attached to/detached from a bolt B. For the turn table 27, its rotational axis can be inclined in a desired direction, and constantly, its rotary shaft is vertically held by a spring. The turn table 27 is provided on a rotary table which is capable of horizontally oscillating to the elevation table 19. By desired inclination of the turn table 27, and horizontal oscillation of the rotary table, the nut N on the turn table 27 is provided with a self-aligning effect on the bolt B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the mounting and dismounting of nuts, which are also used for attaching and detaching giant nuts to and from giant bolts for tightening a horizontal butt flange of a high pressure casing of a main turbine in a nuclear power plant, for example. It concerns the device.

[0002]

2. Description of the Related Art A horizontal butting flange portion of a high pressure casing of a main turbine in a nuclear power plant is fastened by a bolt penetrating substantially vertically and a nut screwed into the bolt from below. Bolts and nuts are both huge, weighing about 50 kg. There is a through hole in the axis of the bolt, through which a wire that locks the nut is passed, and this is pulled up from above the bolt by human power to support the nut in a suspended state. Work is taking place. All of these tasks are performed manually in a small space, resulting in dangerous and heavy labor.

[0003]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an apparatus capable of safely and easily mounting and removing a large nut as described above.

[0004]

In the present invention, in order to solve the above-mentioned problems, a slide table 12 is provided on a carriage 2 movable on a floor F so as to be horizontally movable in the front-rear direction. An elevating table 19 is provided on the elevating table 12 so as to be vertically movable, and a turntable 27 is provided on the elevating table 19 so as to be rotatable substantially horizontally. 1. The lifting table 19 is raised and lowered by lifting means such as the air cylinder 18, and the turntable 27 is rotated forward and reverse by rotating means such as the air motor 37, and the nut N is attached to and detached from the bolt B. The turntable 27 is mounted on the trolley 2 together with the slide table 12.
To facilitate access to the space under the narrow bolt. Further, the lifting table 19 is tilted so that the rotation axis of the turntable 27 is inclined in an arbitrary direction with respect to the vertical.
In addition, the nut N can be self-centered by being able to freely tilt within a predetermined angle range and elastically supported by a spring 34 or the like so as to hold the rotating shaft vertically.
Further, the turntable 27 is provided on the elevating table 19 via the swivel table 25, and the swivel table 25 is supported on the elevating table 19 so as to be swivelable substantially horizontally within a predetermined angle range. The mind has been further enhanced.

[0005]

Embodiments of the present invention will be described with reference to the drawings. 1 is a front view of the nut attaching / detaching device, FIG. 2 is a plan view of the nut attaching / detaching device, FIG. 3 is a side view of the nut attaching / detaching device, FIG.
FIG. 5 is a plan view in which a part of the nut attaching / detaching device is cut away, and FIG.
FIG. 7 is a side view in which a part of the nut attaching / detaching device is cut away, and FIG. 7 is a sectional view near a turntable.

In FIG. 1, a nut attaching / detaching device 1 is formed on a carriage 2 movable on a floor F by casters 3. The bogie 2 has a rectangular main frame 7 composed of a pair of left and right main rods 4 extending in parallel in the front-rear direction, and a connecting plate 5 and a connecting rod 6 connecting the main rods 4 at right and left ends at front and rear ends. Having. The casters 3 are supported by support legs 8 projecting outward from the four corners of the main frame 7. The caster 3 is supported by screwing a main shaft 9 perpendicular to the support leg 8. If the caster 3 is pulled up with respect to the support leg 4, the carriage 2 can be fixed on the floor surface F by touching the floor 2. A handle 10 for moving the carriage 2 is attached to the rear end of the main frame 7. A linear guide 11 is fixed inside the main rod 4 of the main frame 7 along the main rod 4.

The slide table 12 is mounted on the main frame 7 of the carriage 2 so as to be movable in the front-rear direction. That is, the slide table 12 is mounted on the main frame 7.
A pair of parallel supporting plates 13 extending along the inside of the main rod 4
And a base plate 14 that connects the rear ends of the support plates 13 and 13 at right angles to each other to form a U-shaped frame body that opens forward. A slider 15 is fixed to the outside of each of the support plates 13 in the front-rear position.
Are slidably engaged with. At four corners of the base plate 14, guide columns 16 are erected vertically, and are connected at the upper end by a rectangular frame-shaped top plate 17. In the center of the base plate 14,
An air cylinder 18 stands upright.

The elevating table 19 includes an elevating table main body 20 having a horizontal plate shape, an upright plate portion 21 vertically rising from a rear end thereof, and a top plate portion 22 extending horizontally rearward from an upper end of the upright plate portion 21. Having. The top plate portion 22 is located below the top plate 17 of the slide table 12, and the guide column 16 slidably penetrates it. A guide tube 23 is fixed to a lower portion of the side surface of the upright plate portion 21 and a lower surface of the top plate portion 22. The guide cylinder 23 is slidably engaged with the guide column 16. The upper end of the piston rod 18 a of the air cylinder 18 is connected to the top plate 22. Therefore, the elevating table 19 can be vertically moved up and down along the guide columns 16 by the air cylinder 18 as the elevating means.

A slide plate 24 made of a polymer resin is fixed on the elevating table main body 20 in an overlapping manner, and a swivel table 25 is arranged on the elevating table body 20 so as to be horizontally swivelable within a predetermined angle range. That is, the turning table 25 is pivotally supported at the center by the vertical pivot 26 at the center of the elevating table body 20. The swivel table 25 horizontally swivels within an angle range in which the swivel table 25 comes into contact with side edges rising from the left and right sides of the lifting table main body 20.

The turntable 27 is for rotating the nut N mounted thereon, and is provided on the revolving table 25 so as to be rotatable substantially horizontally. That is, the turning table 2
A rotary plate 29 is horizontally rotatably supported on bearing 5 via a bearing 28, and a turntable 27 is provided on this rotary plate 29 via a spherical bearing 30 so as to be horizontally rotatable. On the lower surface of the rotating plate 29, a passive pulley 31 is provided.
Is fixed. On the upper surface of the rotating plate 29, a plurality of drive pins 32 are vertically implanted on the concentric circumference of the rotation shaft.
Loosely accepted. The drive pin 32 is
Can be relatively inclined within. The turntable 27 is elastically supported on a plurality of springs 34 fitted concentrically around the rotating plate 29 so as to maintain a substantially horizontal position. On the upper surface of the turntable 27, three engagement pins 35 are implanted on a concentric circumference of the rotation shaft,
This engages with the engagement groove Na on the lower surface of the nut N. A rolling ball 36 is rotatably fitted to the upper end of the engaging pin 35, and can be easily aligned with the lower surface of the nut N by rolling contact with the nut N when the nut N is removed.

An air motor 37 as a rotating means of the turntable 27 is mounted on the swivel table 25 via a pedestal 38. Rotary shaft 37 of air motor 37
a projects into the lower space of the pedestal 38, and the drive pulley 39 is fixed to this. Drive pulley 39 and passive pulley 3
1 and the belt 40 is wound around the air motor 37.
Is transmitted to the rotating plate 29, the drive pin 32, and the turntable 27.

A centering guide 41 is provided on the swivel table 25 adjacent to the turntable 27 so that the distance to the turntable 27 can be adjusted. Centering guide 41
An arc-shaped guide surface is provided along the outer periphery of the turntable 27, and by contacting the guide surface with the outer periphery of the nut N,
The center of the nut N and the center of the turntable 27 can be roughly adjusted.

On the base plate 14 of the slide table,
A box-shaped cover 42 is fixed so as to cover the guide column 16, and an operation panel 43 is formed on a side surface of the cover 42. The operation panel 43 includes a rotation direction switching valve lever 44, a lifting / lowering switching valve lever 45, a lifting / lowering speed controller 46, a rotation speed controller 47, an emergency stop switch 48, a rotation air regulator 49, a rotation air pressure gauge 50, and a lifting / lowering device. , An air pressure gauge 51 for raising and lowering, and the like.

As shown in FIG. 1, the operation of attaching and detaching a nut N to and from a bolt B vertically penetrating a flange portion A of a main turbine high-pressure casing in a nuclear power plant using a nut attaching and detaching apparatus 1 of this embodiment. The procedure will be described.

When screwing the nut N to the bolt B,
First, the slide table 12 is appropriately pushed forward in accordance with the situation around the bolt B, and the position of the turntable 27 is determined. If the turntable 27 is extended in front of the carriage 2 together with the slide table 12, the narrow bolt B
It is easy to access the lower space. Then, the nut N is placed on the turntable 27 and the engagement pin 35 is engaged with the groove Na. The carriage 2 is moved to bring the nut N almost immediately below the bolt B. Lifting switch valve lever 4
5 is operated to send air to the air cylinder 18 and raise the elevating table 19 to a position where the upper surface of the nut N lightly contacts the lower end of the bolt B. At this time, if there is a misalignment between the bolt B and the nut N, the bogie 2 is moved to perform centering. Next, the lift table 19 is raised while the turntable 27 is rotated clockwise by operating the lever 44 of the rotation direction switching valve, and the nut N is screwed into the bolt B. When the alignment between bolt B and nut N is insufficient,
When the axis of the nut N is inclined with respect to the axis of the bolt B, the biting of the nut N is poor. In such a case, the carriage 2 and the swivel table 25 are made to bite by swinging in the horizontal direction. At this time, the turntable 27
Are tilted appropriately to facilitate alignment. When the screwing of the nut N into the predetermined position is completed, the rotation of the turntable 27 is stopped, the lifting table 19 is lowered to the lower limit position, and the operation is completed.

Next, when the nut N is removed from the bolt B, the carriage 2 is moved, and the center of the turntable 27 is set at a position matching the center of the bolt B. By operating the lever 45 of the lift switching valve, the lift table 19 is raised to a position where the upper end of the engagement pin 35 on the turntable 27 is lightly in contact with the lower surface of the nut N. Perform centering again and operate the lever 44 of the rotation direction switching valve,
Turn the turntable 27 clockwise slowly. At this time, the rolling ball 36 at the tip of the engaging pin 35 rolls on the lower surface of the nut N, and a smooth movement is obtained. Nut engagement groove Na
The rotation is stopped when the engagement pin 35 matches with. Next, the lifting table 19 is raised, and after confirming that the engagement pin 35 has engaged with the engagement groove Na of the nut N, the turntable 27 is rotated counterclockwise to lower the nut N. During this time, the air cylinder 18 is in the ascending mode, but since the nut N descends with a predetermined torque according to the screw pitch, the elevating table 19 is pushed by the nut N and descends. When the nut N comes off from the lower end of the bolt B, only the weight of the nut N is applied to the lifting table 19, and the lifting table 19 holds the nut N at that position. After visually confirming that the nut N has come off from the lower end of the bolt B, the rotation of the turntable 27 is stopped, and the lever 45 of the lift switching valve is operated for the first time to lower the lift table 19 to lower the lower limit position. Work is completed.

According to the weight of the nut to which the present device is applied,
The air pressure sent to the air cylinder 18 is adjusted in advance by the lifting air regulator 51 while watching the lifting air pressure gauge 52. Further, while observing the rotation air pressure gauge 50, the rotation air regulator 49 is adjusted to obtain a desired rotation torque of the turntable 27.

The present invention is not limited to the illustrated embodiment. For example, the lifting and lowering of the lifting table 19 and the rotation of the turntable 27 can be performed by an electric motor instead of an air motor and an air cylinder. .

[0019]

As described above, according to the present invention, the slide table 12 is provided on the carriage 2 movable on the floor F so as to be horizontally movable in the front-rear direction. An elevating table 19 is provided so as to be vertically movable,
A turntable 27 is provided on the elevating table 19 so as to be rotatable substantially horizontally, and the attachment / detachment device 1 is configured so that a nut N is mounted on the turntable 27 and rotated. The lifting table 19 is raised and lowered by lifting means such as the air cylinder 18 and the turntable 27 is moved by the air motor 3.
The nut N is attached to and detached from the bolt B by rotating it forward and backward by a rotating means such as 7. If the turntable 27 projects in front of the bogie 2 together with the slide table 12, there is an effect that it becomes easy to approach a narrow space below the bolt B.

Further, the rotation axis of the turntable 27 can be freely tilted within a predetermined angle range with respect to the elevating table 19 so as to be tilted in an arbitrary direction with respect to the vertical.
Since the rotation shaft is elastically supported by the spring 34 or the like so as to be held vertically, the self-centering property of the nut N is provided.

Further, the turntable 27 is provided on the elevating table 19 via the swivel table 25, and the swivel table 25 is supported on the elevating table 19 so as to be swivelable substantially horizontally within a predetermined angle range. Alignment is further enhanced, and an effect that alignment with the bolt B can be performed more easily is achieved.

[Brief description of the drawings]

FIG. 1 is a front view of a nut attaching / detaching device.

FIG. 2 is a plan view of the nut attaching / detaching device.

FIG. 3 is a side view of the nut attaching / detaching device.

FIG. 4 is a front view in which a part of the nut attaching / detaching device is cut away.

FIG. 5 is a plan view in which a part of the nut attaching / detaching device is cut away.

FIG. 6 is a side view in which a part of the nut attaching / detaching device is cut away.

FIG. 7 is a sectional view near a turntable.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Nut attaching / detaching apparatus 2 Cart 3 Caster 11 Linear guide 15 Slider 12 Slide table 18 Air cylinder (elevating means) 19 Elevating table 20 Air motor (rotating means) 25 Swivel table 27 Turntable 30 Spherical bearing 34 Spring B Bolt F Floor N nut

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tadao Fukuda 6-5-19 Minamishinagawa, Shinagawa-ku, Tokyo Sanwa Tekki Co., Ltd. (72) Eijiro Kojima 6-5 Minamishinagawa, Shinagawa-ku, Tokyo No. 19 Inside Sanwa Tekki Co., Ltd. (72) Inventor Takuya Osawa Inside Sanwa Tekki Co., Ltd. 6-5-19 Minamishinagawa, Shinagawa-ku, Tokyo

Claims (6)

[Claims] An apparatus for attaching and detaching a nut to and from a bolt positioned above a floor surface and having a shaft portion oriented substantially vertically toward the floor surface, comprising: a trolley movable on the floor surface; A slide table supported on the carriage so as to be horizontally movable in the front-rear direction; a lifting table provided vertically on the slide table so as to be vertically movable; and the lifting table for rotating the nut on the upper part. A turntable provided on the slide table so as to be rotatable substantially horizontally, an elevating means provided on the slide table for elevating the elevating table, and a rotating means for rotating the turntable forward and reverse. The lifting table is raised and lowered while the nut is placed and the turntable is rotated, so that the nut is attached to and detached from the bolt. Large nut of the attachment apparatus that. 2. The turntable can be freely tilted within a predetermined angle range with respect to the elevating table so as to tilt the rotation axis in an arbitrary direction with respect to the vertical, and holds the rotation axis vertically. The large-sized nut attaching / detaching device according to claim 1, wherein the large-sized nut attaching / detaching device is elastically supported. 3. The method according to claim 1, wherein the turntable is provided on the lift table via a turntable, and the turntable is provided on the lift table so as to be able to turn substantially horizontally within a predetermined angle range. Claim 1.
Or a device for attaching and detaching a large nut according to 2. 4. The lifting table includes a guide cylinder slidably engaged with a guide column vertically provided on the slide table, and the lifting means is provided vertically on the slide table. 4. The large nut attaching / detaching device according to claim 1, wherein the rotating unit comprises an air motor fixed on the swivel table. 5. The turntable is connected via a spherical bearing at the center between the turntable and a rotary plate supported on the swivel table so as to be horizontally rotatable and connected to a rotary shaft of the air motor. The lower part of the periphery is supported by a plurality of springs so that it is always horizontal, and the drive pin protruding from the rotating plate in the recess of the periphery is loosely received, and rotation is transmitted while allowing the inclination of the rotation axis. The large-sized nut attaching / detaching device according to claim 4, wherein 6. A pair of left and right parallel linear guides extending in the front-rear direction are provided on the carriage, and sliders slidably engaged with the linear guides are attached to both right and left edges of the slide table. The attachment / detachment device for a large nut according to claim 1, wherein: